Silicon fertilisation affects morphological and immune defences of an insect pest and enhances plant compensatory growth

Journal of Pest Science, Journal Year: 2022, Volume and Issue: 96(1), P. 41 - 53

Published: Jan. 13, 2022

Abstract Herbivorous insects have evolved various anti-predator defences, including morphological, behavioural, and immune which can make biocontrol of herbivorous pests challenging. Silicon (Si) accumulation in plants is a potent physical defence against mandibulate insects. However, it remains uncertain how Si affects the defences insect herbivores plant following herbivory. We grew model grass, Brachypodium distachyon , hydroponically with (+Si) or without (–Si) investigated plant-mediated effects on cotton bollworm, Helicoverpa armigera integrating morphological (i.e. integument resistance thickness), defences. also examined compensatory growth leaf trichome production. Larval growth, consumption, were lower when feeding +Si compared to –Si plants. thickness, defensive behaviours, haemocyte density, lysozyme-like activity haemolymph unaffected by Si. Larvae fed had higher phenoloxidase (PO) total-PO activities than larvae plants, although this did not enhance melanisation response larvae. Furthermore, supplies increased compensation for herbivory constitutive production, whereas induced production only provide first evidence an herbivore. suggest that Si-supplemented could contribute their vulnerability natural enemies high PO may impose fitness costs (e.g. delayed development).

Language: Английский

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Silica and Selenium Nanoparticles Attract or Repel Scale Insects by Altering Physicochemical Leaf Traits

Plants, Journal Year: 2024, Volume and Issue: 13(7), P. 952 - 952

Published: March 25, 2024

Although nanoparticles have gained attention as efficient alternatives to conventional agricultural chemicals, there is limited knowledge regarding their effects on herbivorous insect behavior and plant physicochemistry. Here, we investigated the of foliar applications nano-silica (SiO2NPs) nano-selenium (SeNPs), bulk-size silica (SiO2) choice arrowhead scale mandarin orange plants. One leaf a bifoliate pair was treated with one three while other water (control). The respective SiO2, SeO2, calcium (Ca), carbon (C) content levels in epidermis mesophyll were quantified using SEM–EDX (or SEM–EDS); toughness density body size measured. First-instar nymphs preferred silica-treated leaves avoided SeNP-treated leaves. SiO2 did not differ between control SiO2NP-treated leaves, but higher SiO2-treated level SiO2NP treatment compared that treatment. Silica-treated increased toughness, not; mesophyllic content. per and, treatment, epidermal C There no correlation SeO2 density. This study highlights potential uses SeNPs an deterrent for enhancing attracting insects.

Language: Английский

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Role of silicon in legume‐insect interactions: Insights from a plant experiencing different levels of herbivory

Functional Ecology, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 12, 2024

Abstract Silicon (Si) supplementation can enhance symbiotic functions in some legumes (Fabaceae) with their nitrogen‐fixing rhizobia, such as root nodulation and nitrogen fixation. However, it is still poorly understood how Si influences legume–insect interactions. Here, we investigated a legume responds not only to but also herbivory treatment varying infestation levels two events. We conducted controlled climate chamber experiment by growing Medicago truncatula plants inoculated rhizobia. For half of the plants, soil was kept without (−Si), whereas other regularly supplemented (+Si). then infested caterpillars Spodoptera littoralis 0, 1 or 3 larvae larva single attack double attack, respectively. To understand plant responses combinations, examined 16 functional traits. Nodule number, nodule fresh mass leghaemoglobin concentrations were affected plants. increasing led decreases measured traits Foliar C N ratio increased decreased herbivory, indicating contrasting resource allocation. Herbivory did affect content foliar Si, which higher +Si than −Si reduced phenolics suggesting potential trade‐off between silicification phenolic production. trichome densities patterns less clear biomass Relative growth rates caterpillars, proxy for resistance, mainly due treatment, when fed on Using trait‐based approach, provide novel insights better response different conclude that predominantly exerts much stronger effects various traits, pointing necessity respond induced defence strategies. Read free Plain Language Summary this article Journal blog.

Language: Английский

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Siliceous and non‐nutritious: Nitrogen limitation increases anti‐herbivore silicon defences in a model grass

Journal of Ecology, Journal Year: 2021, Volume and Issue: 109(11), P. 3767 - 3778

Published: July 29, 2021

Abstract Silicon (Si) accumulation alleviates a diverse array of environmental stresses in many plants, including conferring physical resistance against insect herbivores. It has been hypothesised that grasses, particular, utilise ‘low metabolic cost’ Si for structural and defensive roles under nutrient limitation. While carbon (C) concentrations often negatively correlate with concentrations, the relationship between nitrogen (N) status is more variable. Moreover, impacts N limitation on constitutive defences (e.g. silica prickle cells) herbivores are unknown. We determined how affected deposition model grass Brachypodium distachyon changes these impacted herbivore Helicoverpa armigera growth rates. used scanning electron microscopy (SEM) energy dispersive X‐ray spectrometry conjunction mapping (XRM) to quantify structures leaves determine patterns. also supply jasmonic acid (JA) pathway, master regulator induced arthropod reduced shoot by over 40%, but increased root mass (+21%), leaf (+50%) density (+28%) flattened (+76%) cells. Energy‐dispersive spectroscopy XRM established was being deposited structures, together hooked cells macro‐hairs. Herbivore relative rates (RGR) were than 115% lower Si‐supplied plants compared without correlated concentration cell density. RGR further positively concentrations. Increases JA following induction pathway at least doubled Synthesis . highly regulated availability, promoting both line resource availability hypothesis. These results indicate grasses use ‘low‐cost Si’ when resources limited suggest plant productivity may benefit from optimising conventional fertilisers fertilisation.

Language: Английский

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Silicon Defence in Plants: Does Herbivore Identity Matter?

Trends in Plant Science, Journal Year: 2020, Volume and Issue: 26(2), P. 99 - 101

Published: Nov. 13, 2020

Language: Английский

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